Dutch Primary Care Rule for DVT

Dutch Primary Care Rule for DVT
Sign or Symptom:
[select name="variable_1" value="No (0 points)=0|Yes (1 point)=1"] <-- Absence of leg trauma?
[select name="variable_2" value="No (0 points)=0|Yes (1 point)=1"] <-- Active cancer (treatment within 6 months, or palliation)?
[select name="variable_3" value="No (0 points)=0|Yes (2 points)=2"] <-- Calf swelling of 3 cm or more compared with the contralateral leg when measured 10 cm below the tibial tuberosity?
[select name="variable_4" value="No (0 points)=0|Yes (1 point)=1"] <-- Collateral dilation of nonvaricose superficial veins?
[select name="variable_5" value="No (0 points)=0|Yes (1 point)=1"] <-- Male sex?
[select name="variable_6" value="No (0 points)=0|Yes (1 point)=1"] <-- Recently bedridden for more than 3 days or major surgery requiring general or regional anesthesia within the previous 12 weeks?
[select name="variable_7" value="No (0 points)=0|Yes (1 point)=1"] <-- Use of oral contraceptives?
[select name="variable_8" value="No (0 points)=0|Yes (6 points)=6"] <-- Positive D-dimer result (0.5 mcg per mL or greater or 1.7 mol per L or greater)?
Score: [calc memo="number" value="score=(variable_1)+(variable_2)+(variable_3)+(variable_4)+(variable_5)+(variable_6)+(variable_7)+(variable_8)"] out of 14 points (3 points or less is a negative screen)
Recommendation --> [calc memo="result" value="score=(variable_1)+(variable_2)+(variable_3)+(variable_4)+(variable_5)+(variable_6)+(variable_7)+(variable_8);score>2?'Doppler ultrasonography of the affected leg is recommended':'Low risk for DVT, ultrasonography is not indicated'"]
[checkbox memo="display/hide references" name="footnotes" value=""][conditional field="footnotes" condition="(footnotes).is('')"]
reference:
[link url="//www.ncbi.nlm.nih.gov/pubmed/21242558" memo="#1"] van der Velde EF, Toll DB, Ten Cate-Hoek AJ, et al. Comparing the diagnostic performance of 2 clinical decision rules to rule out deep vein thrombosis in primary care patients. Ann Fam Med. 2011;9(1):31–36. 
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